Fix showing empty view in mobile device view (#407)

app/src/main/java/io/github/wulkanowy/data/repositories/mobiledevice/MobileDeviceRepository.kt

@@ -35,10 +35,18 @@ class MobileDeviceRepository @Inject constructor(
     }
 
     fun unregisterDevice(semester: Semester, device: MobileDevice): Single<Boolean> {
-        return remote.unregisterDevice(semester, device)
+        return ReactiveNetwork.checkInternetConnectivity(settings)
+            .flatMap {
+                if (it) remote.unregisterDevice(semester, device)
+                else Single.error(UnknownHostException())
+            }
     }
 
     fun getToken(semester: Semester): Single<MobileDeviceToken> {
-        return remote.getToken(semester)
+        return ReactiveNetwork.checkInternetConnectivity(settings)
+            .flatMap {
+                if (it) remote.getToken(semester)
+                else Single.error(UnknownHostException())
+            }
     }
 }

app/src/main/java/io/github/wulkanowy/ui/modules/mobiledevice/MobileDeviceAdapter.kt

@@ -6,5 +6,5 @@ import io.github.wulkanowy.data.db.entities.MobileDevice
 
 class MobileDeviceAdapter<T : IFlexible<*>> : FlexibleAdapter<T>(null, null, true) {
 
-    var onDeviceUnregisterListener: (MobileDevice, position: Int) -> Unit = {  _, _ -> }
+    var onDeviceUnregisterListener: (device: MobileDevice, position: Int) -> Unit = { _, _ -> }
 }

app/src/main/java/io/github/wulkanowy/ui/modules/mobiledevice/MobileDeviceFragment.kt

@@ -8,10 +8,10 @@ import android.view.View.VISIBLE
 import android.view.ViewGroup
 import eu.davidea.flexibleadapter.common.FlexibleItemDecoration
 import eu.davidea.flexibleadapter.common.SmoothScrollLinearLayoutManager
-import eu.davidea.flexibleadapter.helpers.EmptyViewHelper
 import eu.davidea.flexibleadapter.helpers.UndoHelper
 import eu.davidea.flexibleadapter.items.AbstractFlexibleItem
 import io.github.wulkanowy.R
+import io.github.wulkanowy.data.db.entities.MobileDevice
 import io.github.wulkanowy.ui.base.BaseFragment
 import io.github.wulkanowy.ui.modules.main.MainActivity
 import io.github.wulkanowy.ui.modules.main.MainView
@@ -48,7 +48,7 @@ class MobileDeviceFragment : BaseFragment(), MobileDeviceView, MainView.TitledVi
     }
 
     override fun initView() {
-        mobileDevicesRecycler.run {
+        with(mobileDevicesRecycler) {
             layoutManager = SmoothScrollLinearLayoutManager(context)
             adapter = devicesAdapter
             addItemDecoration(FlexibleItemDecoration(context)
@@ -56,37 +56,43 @@ class MobileDeviceFragment : BaseFragment(), MobileDeviceView, MainView.TitledVi
                 .withDrawDividerOnLastItem(false)
             )
         }
-        EmptyViewHelper.create(devicesAdapter, mobileDevicesEmpty)
+        with(devicesAdapter) {
+            isPermanentDelete = false
+            onDeviceUnregisterListener = presenter::onUnregisterDevice
+        }
         mobileDevicesSwipe.setOnRefreshListener { presenter.onSwipeRefresh() }
         mobileDeviceAddButton.setOnClickListener { presenter.onRegisterDevice() }
-        devicesAdapter.run {
-            isPermanentDelete = false
-            onDeviceUnregisterListener = { device, position ->
-                val onActionListener = object : UndoHelper.OnActionListener {
-                    override fun onActionConfirmed(action: Int, event: Int) {
-                        presenter.onUnregister(device)
-                    }
-
-                    override fun onActionCanceled(action: Int, positions: MutableList<Int>?) {
-                        devicesAdapter.restoreDeletedItems()
-                    }
-                }
-                UndoHelper(devicesAdapter, onActionListener)
-                    .withConsecutive(false)
-                    .withAction(UndoHelper.Action.REMOVE)
-                    .start(listOf(position), mobileDevicesRecycler, R.string.mobile_device_removed, R.string.all_undo, 3000)
-            }
-        }
     }
 
     override fun updateData(data: List<MobileDeviceItem>) {
         devicesAdapter.updateDataSet(data)
     }
 
+    override fun restoreDeleteItem() {
+        devicesAdapter.restoreDeletedItems()
+    }
+
     override fun clearData() {
         devicesAdapter.clear()
     }
 
+    override fun showUndo(position: Int, device: MobileDevice) {
+        val onActionListener = object : UndoHelper.OnActionListener {
+            override fun onActionConfirmed(action: Int, event: Int) {
+                presenter.onUnregisterConfirmed(device)
+            }
+
+            override fun onActionCanceled(action: Int, positions: MutableList<Int>?) {
+                presenter.onUnregisterCancelled()
+            }
+        }
+
+        UndoHelper(devicesAdapter, onActionListener)
+            .withConsecutive(false)
+            .withAction(UndoHelper.Action.REMOVE)
+            .start(listOf(position), mobileDevicesRecycler, R.string.mobile_device_removed, R.string.all_undo, 3000)
+    }
+
     override fun hideRefresh() {
         mobileDevicesSwipe.isRefreshing = false
     }
@@ -95,6 +101,10 @@ class MobileDeviceFragment : BaseFragment(), MobileDeviceView, MainView.TitledVi
         mobileDevicesProgress.visibility = if (show) VISIBLE else GONE
     }
 
+    override fun showEmpty(show: Boolean) {
+        mobileDevicesEmpty.visibility = if (show) VISIBLE else GONE
+    }
+
     override fun enableSwipe(enable: Boolean) {
         mobileDevicesSwipe.isEnabled = enable
     }

app/src/main/java/io/github/wulkanowy/ui/modules/mobiledevice/MobileDevicePresenter.kt

@@ -50,6 +50,7 @@ class MobileDevicePresenter @Inject constructor(
                 view?.run {
                     updateData(it)
                     showContent(it.isNotEmpty())
+                    showEmpty(it.isEmpty())
                 }
                 analytics.logEvent("load_devices", "items" to it.size, "force_refresh" to forceRefresh)
             }) {
@@ -62,13 +63,27 @@ class MobileDevicePresenter @Inject constructor(
         view?.showTokenDialog()
     }
 
-    fun onUnregister(device: MobileDevice) {
+    fun onUnregisterDevice(device: MobileDevice, position: Int) {
+        view?.run {
+            showUndo(position, device)
+            showEmpty(isViewEmpty)
+        }
+    }
+
+    fun onUnregisterCancelled() {
+        view?.run {
+            restoreDeleteItem()
+            showEmpty(isViewEmpty)
+        }
+    }
+
+    fun onUnregisterConfirmed(device: MobileDevice) {
         Timber.i("Unregister device started")
         disposable.add(studentRepository.getCurrentStudent()
             .flatMap { semesterRepository.getCurrentSemester(it) }
             .flatMap { semester ->
                 mobileDeviceRepository.unregisterDevice(semester, device)
-                .flatMap { mobileDeviceRepository.getDevices(semester, it) }
+                    .flatMap { mobileDeviceRepository.getDevices(semester, it) }
             }
             .map { items -> items.map { MobileDeviceItem(it) } }
             .subscribeOn(schedulers.backgroundThread)
@@ -84,6 +99,7 @@ class MobileDevicePresenter @Inject constructor(
                 view?.run {
                     updateData(it)
                     showContent(it.isNotEmpty())
+                    showEmpty(it.isEmpty())
                 }
             }) {
                 Timber.i("Unregister device result: An exception occurred")

app/src/main/java/io/github/wulkanowy/ui/modules/mobiledevice/MobileDeviceView.kt

@@ -1,5 +1,6 @@
 package io.github.wulkanowy.ui.modules.mobiledevice
 
+import io.github.wulkanowy.data.db.entities.MobileDevice
 import io.github.wulkanowy.ui.base.BaseView
 
 interface MobileDeviceView : BaseView {
@@ -10,6 +11,8 @@ interface MobileDeviceView : BaseView {
 
     fun updateData(data: List<MobileDeviceItem>)
 
+    fun restoreDeleteItem()
+
     fun hideRefresh()
 
     fun clearData()
@@ -20,5 +23,9 @@ interface MobileDeviceView : BaseView {
 
     fun showContent(show: Boolean)
 
+    fun showEmpty(show: Boolean)
+
+    fun showUndo(position: Int, device: MobileDevice)
+
     fun showTokenDialog()
 }

app/src/main/res/layout/fragment_mobile_device.xml

@@ -20,7 +20,7 @@
         android:gravity="center"
         android:orientation="vertical"
         android:padding="10dp"
-        android:alpha="0.0">
+        android:visibility="gone">
 
         <TextView
             android:layout_width="wrap_content"